Tag Archives: VMWARE

Nutanix customers love the fact we give them their weekends back by having 1-click upgrades for the Acropolis operating system, BIOS, BMC, Firmware and the Hypervisor. When speaking to some customers still go through a multi-step process to include:

Download Updates in VUM
Create a new baseline
Attach Hosts to baseline and scan hosts to validate
Place DRS to manual and evacuate guests from the host
Issue shutdown command to CVM
Place host into maintenance mode
Proceed with remediation wizard
Complete upgrade
Reboot host
Power on CVM
Validate RF in Prism and move on

Yes, a couple of these steps are added compared to non-Nutanix environments, however there are still a number of steps that need to be completed.

With Prism, as long as the cluster is managed with vCenter, we are able to manage the entire process for you, by simply opening the upgrade tab, uploading the offline upgrade package with the json file from the Nutanix support portal and off you go! It’s as simple as that, and here’s another video to show the process.

Learn important aspects of vSphere including administration, security, performance, and configuring vSphere Management Assistant (VMA) to run commands and scripts without the need to authenticate every attempt

VMware ESXi 5.1 Cookbook is a recipe-based guide to the administration of VMware vSphere

I’ve been working with VMware products for a number of years now and this book looked like a beginners guide. I was also a little disappointed that the book was based on vSphere 5.1 and not the most current release vSphere 5.5 even though the current release of vSphere was out 6 months before the book.

Who is the book for?

The book is primarily written for technical professionals with system administration skills and basic knowledge of virtualization who wish to learn installation, configuration, and administration of vSphere 5.1. Essential virtualization and ESX or ESXi knowledge is advantageous.

I personally would say it was for people who were new to Virtualization or deploying VMware vSphere products for the first time. Perhaps even a useful resource for management or project management who want to delve a little deeper into the technology. Virtualization concepts would be advantageous, however the book covers each step of a basic installation in good detail.

Areas Covered

The book is split into 9 chapters, aimed at covering a cradle to grave ‘basic’ vSphere installation.

Installing and Configuring ESXi

Installing and Using vCenter

Networking

Storage

Resource Management and High Availability

Managing Virtual Machines

Securing the ESXi Server and Virtual Machines

Performance Monitoring and Alerts

vSphere update Manager

The book reads and flows well, with the explanations clear and concise. The author does a good job explaining all concepts covered in the book.

Final Thoughts

If you are a seasoned vSphere administrator/architect this book probably isn’t for you. Saying this, it does act as a handy reference if there are areas of vSphere that you aren’t familiar with that you need to review. One thing I do like about this book, is all screenshots (where possible) are taken from the vSphere Web Client. As many of us know, the Web Client will be the only way to manage VMware infrastructure in the not too distant future, therefore for the old skool folk like myself it also acts as a handy reference to help complete tasks in this manner.

Overall, I would say the author has done a great job in what they set out to do. Create a quick fire reference for vSphere administration tasks.

“Why do I need to bother backing up the config file of my vCNS Manager, can’t I just snapshot it?”

It’s a good question, and one that involved a little lab testing to play around with.

If you were to snapshot your vCNS manager,which does work from testing in my lab (albeit limited functional testing), then you are able to restore the vCNS manager from snapshot fairly efficiently and quickly.

The questions I then thought of were:

When is the backup window? (if there is one)

How often would a vCNS snapshot be taken?

How busy is the vCNS manager?

Does a backup restore involve change control or other teams?

The reason for these questions in my head were simple.

If a vCNS manager was in a relatively busy vCloud environment deploying a number of Edge devices daily, then yes they would continue to run if the manager were to fail, but if the vCNS manager were only scheduled to have a daily snapshot during a nightly backup window, then there could be an issue with unknown Edge devices after the restore from backup.

The official supported method of backing up vCNS manager is to schedule a backup from the manager itself, to backup the configuration to an FTP/SFTP site.

If the vCNS manager were to fail, you would simply deploy a new vCNS manager (normally within minutes) then re-apply the last saved configuration and get back up and running fairly quickly. Yes, you could argue that if only a single backup was taken daily then we would be in the same boat as with a snapshot, however, It’s much easier and more manageable, in my opinion, to set perhaps an hourly backup (in busy environments) and perhaps only keep a days worth of backup files.

After some debate with my client, my recommendation was to ‘keep it simple’. This meant, stay within the realms of vendor recommendation and support. Configure an hourly backup and keep a single days worth of backups. In the case of a failed and unrecoverable vCNS manger, deploy a new appliance and restore the configuration.

I’d be interested to hear any feedback from others as to what they do in their environments or in fact recommend to others.

I was trying to access the VMRC of a VM residing in a vApp in a clients vCD setup and kept being prompted with the following error:

Now, I’m used to seeing the following warning when trying to access vCD using Chrome or Safari, but I was using IE11 at the time…

I did some snooping around and saw that a few people had posted about receiving the same error message and had various fixes, none of which worked in my case. So I tweeted out a statement to see if IE11 was actually supported. the guys who look after the VMware KB twitter account were quick to respond pointing me to some published KB’s with official supported browsers.

To my surprise, vCD 5.1 only supports up to IE9, hence the error message appearing. vCD 5.5 brings some support for further browsers.

I wasn’t aware of the restrictions, however it’s good to know. Check out the KB articles (links below) to see the latest supported browsers.

Understand what logical performance services are provided by VMware solutions

VMware have a number of performance enhancers in the vSphere, some of which are available in all licence versions, some however require a certain licence level to make the features available.

Memory

Transparent Page Sharing – Shares identical memory pages across multiple VMs. This is enabled by default. Consideration should be given to try and place similar workloads on the same hosts to gain maximum benefit.

Memory Ballooning – Controls a balloon driver which is running inside each VM. When the physical host runs out of memory it instructs the driver to inflate by allocating inactive physical pages. The ESXi host can uses these pages to fulfill the demand from other VMs.

Memory Compression – Prior to swapping, memory pages out to physical disks. The ESXi server starts to compress pages. Compared to swapping, compression can improve the overall performance in an memory over commitment scenario.

Swapping – As the last resort, ESXi will start to swap pages out to physical disk.

Storage I/O Control (SIOC) – was introduced in vSphere 4.1 and allows for cluster wide control of disk resources. The primary aim is to prevent a single VM on a single ESX host from hogging all the I/O bandwidth to a shared datastore. An example could be a low priority VM which runs a data mining type application impacting the performance of other more important business VMs sharing the same datastore.

vSphere Storage API’s – Storage Awareness (VASA) – VASA is a set of APIs that permits storage arrays to integrate with vCenter for management functionality.

Networking

Network IO Control (NIOC) – When network I/O control is enabled, distributed switch traffic is divided into the following predefined network resource pools: Fault Tolerance traffic, iSCSI traffic, vMotion traffic, management traffic, vSphere Replication (VR) traffic, NFS traffic, and virtual machine traffic. You can control the bandwidth each network resource pool is given by setting the physical adapter shares and host limit for each network resource pool.

List the key performance indicators for resource utilisation

According to ITIL, a Key Performance Indicator (KPI) is used to assess if a defined service is running according to expectations. The exact definition of the KPIs differs depending on the area. This objective is about server performance which is typically assessed using the following KPIs: Processor, Memory, Disk, and Network.

On Friday morning I sat the VCAP5-DCD exam and I’m delighted to say I passed! If you are a regular visitor, you’ll notice that I have started a VCAP-DCD study guide section which hasn’t been updated in a while. I wont bore you with why, however I do have all my study notes, which I will collate and continue posting alongside the relevant objectives.

Usual Disclaimer: I agreed to the NDA prior to sitting the exam so I will not divulge any exam specifics, so please don’t ask!

The exam is tough, as is the common theme with VCAP exams, and test every area of a vSphere deployment. My biggest piece of advise would be get to know the blueprint inside out, it should become your friend, and you should be comfortable with everything in it!

The multiple choice questions are more complex and tougher than those set out in the VCP exams, as you would expect being the advanced certification, however I believe these questions are very fair. The drag and drop style questions are tricky too and require some working out, don’t whizz through these questions, take your time, as I would image these are some big hitters on the overall exam scoring (I don’t know this, I’m just assuming). The Visio style diagram questions are again tough, (see a pattern emerging here?) however contain all the information you need and more to successfully answer the question.

In no particular order, here is what I would recommend to any people planning to sit the exam:

Don’t panic about time, keep calm and work at a consistent pace and you will be fine

Take as many laminate sheets as permitted, I drew my designs on here before doing them on screen so I knew what I wanted to place where, as the tool can be quite clunky

Aside from official VMware documentation, there are a few other resources I would highly recommend to use for study material, they can be found on my VCAP-DCD study guide page.

Last piece of advise would be to draw out some practise designs. Take your client or internal designs, change them and draw them out. Don’t just concentrate on hosts and clusters, include storage and networks too. Use multiple tiers of storage, multiple protocols, and throw in some DR for good measure.

Originally, for my VCAP-DTD study I used some Magic Whiteboard from Amazon, however it’s quite expensive and I went through the roll quite quickly. I’ve since purchased a clear glass dry-erase board and put it on the wall in my home office, which is much more convenient and in my opinion an essential skill that needs to be sharp for the exam!

If you are sitting the exam soon, please keep checking back for updates as I continue to post my notes against each blueprint objective and good luck! What’s next? VCAP-DCA of course!

This was covered off in the previous Objective, however, as a reminder

Availability – The ability of a system or service to perform it’s required function when required. It is usually calculated as a percentage.

Manageability – The expense of running a system. If in a large enterprise the system is managed by a small team, the operation cost can therefore be low.

Performance – The measure of what is delivered by the system. This is usually measured against known standards. Recoverability – The ability to return a system to a working state after a failure or repair.

Security – The process of ensuring the service is used in the appropriate manner.

Understand what logical availability services are provided by VMware solutions.

The two primary availability services in vSphere are High Availability (HA) and Fault Tolerance (FT). Studying for this exam, you should be understand the differences in these features, however at a very high level: HA – Can minimise downtime by restarting VMs in case of a hardware failure FT – Provides continues availability for a VM by making a secondary copy of the VM on another physical host. To gain a better understanding of VMware’s HA, (as well as DRS, Storage DRS and Stretched Clusters) the VMware vSphere 5.1 Clustering Deep Dive by Frank Denneman and Duncan Epping is a MUST! The VMware vSphere Availability Guide is also a MUST read. Fault Tolerance, whist no doubt is a great technology, it does have limitations, which are discussed in the Availability Guide. I rarely see a business case for FT, in most cases HA is good enough.

Availability – The ability of a system or service to perform it’s required function when required. It is usually calculated as a percentage.

Manageability – The expense of running a system. If in a large enterprise the system is managed by a small team, the operation cost can therefore be low.

Performance – The measure of what is delivered by the system. This is usually measured against known standards. Recoverability – The ability to return a system to a working state after a failure or repair.

Security – The process of ensuring the service is used in the appropriate manner.

Describe the concept of redundancy and the risks associated with single points of failure.

A single point of failure is a system component, that if it fails, will then cause the entire system to fail because of it. For example, in a vSphere world, if we have a virtual switch with a single physical NIC uplink and this uplink fails, the virtual switch will fail as a result. These components can be bolstered by adding redundancy, in the above example we could add redundancy to the virtual switch by adding a second physical uplink, therefore if one uplink fails traffic could continue to pass on the second uplink. This spreads out to multiple areas of a vSphere design, hosts in clusters, components in hosts and stretching out to the wider infrastructure, with multiple physical switches, load balancers etc etc.

Differentiate Business Continuity and Disaster Recovery concepts.

Business Continuity is focussing on avoiding or mitigating the impact of risk, therefore is a proactive approach.

Disaster Recovery is focussing on the recovery of a system/service after an outage, therefore is a reactive approach.

VMware offer a free DR/BC Fundamentals training course through MyLearn. Click the following link to register

In preparation for an upcoming project, I’m installing vCAC 5.2 in my home lab. Anyone who has installed vCAC will have used the vCAC prereq checker tool. This tool is simply fantastic. vCAC has a huge amount of prereq’s that need to be configured, this tool does a great job in capturing everything. I like that it provides instructions on how to resolve issues when components need resolving. There is also a ‘Fix Issue’ button which allows for an automated fix of a handful of the requirements.

With the checker reporting I was good to go, I proceeded with the install. All was going well until I came to install the DEM worker and I was met with the following error.

I did a few basic checks to ensure DNS was all good in the lab, however I had no issues there. Upon further investigation I looked to see what services the vCAC Server Setup had installed previously.

There is only one service which is the “VMware vCloud Automation Center Service” and it wasn’t started.

The vCAC server setup allows you to specify a service account to assign to this service, which I had ensured was a local admin on the server. When trying to start the service I got a permission error.

After granting the account the right to ‘Log on as a service’ the service did start and I was able to finish the installation of the DEM worker.

It seems odd to me that the PreReq checker doesn’t prompt for this, as it seems such a comprehensive tool.

Identify basic service dependencies for infrastructure and application services

Service dependencies come in many forms within a vSphere infrastructure design. Services rely on objects such as DNS, NTP, Active Directory etc. What devices are communicating together? What ports are they communicating on? Which processes make up these services?

VMware did have a product to assist in this, VMware vCenter Application Discovery manager, however this has now gone EOL, and unless you have already purchased it, you wont be able to get your hands on it. The current state analysis that should have already been completed at this point should help here, in particular in identifying the applications that will be migrated. It will then be a manual process to discover and document these dependencies.

I found a good WIKI from ServiceNow which delves deeper into application dependency mapping. This article explains how relationships are defined using the following:

Runs on::Runs

Depends on::Used by

Hosted on ::Hosts

Virtualised by::Virtualises

Contains::Contained by

IP Connection::IP Connection

They also delve deeper into upstream and downstream relationships, I’d highly recommend giving this page some attention.

Document and reference your findings to ensure every relationship and dependency is covered and accounted for in the design.